Dual antiplatelet compared to triple antithrombotic therapy in anterior wall acute myocardial infarction complicated by depressed left ventricular ejection fraction Ola O. Oyetayo, PharmD, MSc, Kipp Slicker, DO, Lisa De La Rosa, MD, Wesley Lane, MD, Dane Langsjoen, MD, Chhaya Patel, MD, Kevin Brough, MD, Jeffrey Michel, MD, and Christopher Chiles, MD
Current guidelines recommend triple antithrombotic therapy (TT) consisting of warfarin, aspirin, and a P2Y12 inhibitor following an anterior ST elevation myocardial infarction (STEMI) complicated by extensive wall motion abnormalities. This recommendation, however, is based on data collected before percutaneous coronary intervention (PCI) became the standard of care for the treatment of STEMI. We designed a retrospective study of patients who received PCI for anterior STEMI over an 8-year period to compare rates of thromboembolic and bleeding events between patients receiving dual antiplatelet therapy (DAPT) and those receiving TT, including warfarin. Patients were included if the predischarge echocardiogram showed extensive wall motion abnormality and an ejection fraction ≤35%. Patients with known left ventricular thrombus were excluded. A total of 124 patients met the criteria, with 80 patients in the DAPT group and 44 in the TT group. The median age was 58 years in the TT group and 64 years in the DAPT group (P < 0.04), with an average ejection fraction of 31%. Thromboembolic events occurred in 4 patients (5%) in the DAPT group compared with 3 patients (6.8%) in the TT group (P = 0.70). Bleeding occurred in 2 patients in the DAPT group and 4 patients in the TT group (2.5% in DAPT vs. 9.1% in TT group, P = 0.18). No differences in rates of clinical embolism or left ventricular thrombus were found. Our data support recent findings that warfarin may not be indicated for patients following PCI for anterior STEMI, even when significant wall motion abnormalities and reduced ejection fraction ≤35% are present.
A
cute thromboembolic events due to left ventricular thrombus (LVT) formation, particularly in patients with reduced ejection fraction (EF), remain a risk for patients surviving an anterior ST elevation myocardial infarction (STEMI) (1). The reported incidence of LVT formation and subsequent embolization varies based on the timing of the echocardiographic examination and the diagnostic, anticoagulation, and reperfusion strategies utilized in managing the initial presentation but is noted to range from 0 to as high as 86% (1–9). Warfarin as a prophylactic strategy is therefore utilized and suggested in guidelines based on data derived from pooled results of studies done before catheter-based treatment of STEMI was prominent (10, 11). A recent report by Le May et al has suggested that warfarin treatment might be unnecessary in patients managed by primary PCI and dual antiplatelet therapy (DAPT) (12). The potential adequacy of DAPT alone Proc (Bayl Univ Med Cent) 2015;28(4):445–449
was also shown in a small study that showed no advantage to a triple therapy (TT) regimen involving aspirin, a P2Y12 inhibitor, and warfarin when compared with DAPT with aspirin and a P2Y12 inhibitor in preventing LVT and systemic embolism (13). Given the uncertain benefit and known bleeding risk associated with TT (14), we conducted a retrospective analysis spanning 8 years to compare the rates of LVT formation and thromboembolic events in patients with STEMI with EF ≤35% managed with DAPT alone versus TT. METHODS This was a retrospective, single-center study of patients presenting with anterior wall myocardial infarction (MI) between January 2003 and November 2012 with additional follow-up within 16 weeks of initial discharge at a large academic medical system which serves as the primary STEMI PCI center in the Central Texas region. The study timeline was selected based on availability of electronic medical records for review. Study data were abstracted from the electronic medical record system, which contained both inpatient and outpatient visits. The study received approval from the institutional review board. Patients were identified as having anterior wall MI based on documentation obtained using the ICD-9 codes for initial episode of care for acute anterior MI (410.0, 410.1). These codes were verified on the hospital discharge summary during manual electronic chart review. Subjects had to meet the following inclusion criteria: received primary PCI (including rescue PCI for failed lytic therapy); received aspirin and an additional P2Y12 inhibitor (clopidogrel, prasugrel, or ticagrelor); had a predischarge echocardiogram showing extensive wall motion abnormalities (akinetic or hypokinetic segments); and had an EF ≤35%. Patients were excluded if they did not survive to hospital discharge, required anticoagulation for other indications (atrial fibrillation or valvular disease), had no additional From the Department of Pharmacy Practice, College of Pharmacy, Texas A&M Health Science Center and Baylor Scott & White Health, Temple, Texas (Oyetayo); the Division of Cardiology (Slicker, De La Rosa, Michel, Chiles) and Department of Internal Medicine (Lane, Langsjoen, Patel, Brough), College of Medicine, Texas A&M Health Science Center, and Baylor Scott & White Health, Temple, Texas. Corresponding author: Jeffrey Michel, MD, Baylor Scott & White Health, 2401 South 31st Street, MS-33-ST156, Temple, TX 76508 (e-mail: [email protected]). 445
follow-up within 16 weeks of initial discharge in the system, or had identified thrombus on predischarge echocardiogram. A 16-week follow-up was utilized since current guidelines recommend 3 months of therapy if actively prophylaxing against LVT formation. Patients were treated according to the discretion of the admitting cardiologists at the time of admission. Patients were classified into two groups based on the receipt of oral anticoagulation with warfarin. Patients receiving warfarin therapy in addition to aspirin and an additional P2Y12 agent (clopidogrel, prasugrel, or ticagrelor) at discharge were classified as the TT cohort, whereas patients receiving dual therapy with aspirin and an additional P2Y12 agent (clopidogrel, prasugrel, or ticagrelor) were identified as the DAPT cohort. The primary study outcome was the first occurrence of the composite of LVT, cerebrovascular accident, or systemic embolism. The primary safety endpoint was major bleeding. Other outcomes included the rate of occurrence of the individual components of the primary outcome and total reported bleeding. LVT was defined as a report of possible, probable, or definite thrombus on an echocardiogram. Thromboembolic complications were identified as clinical manifestation of acute cerebral or peripheral ischemia diagnosed with objective testing or the clinical diagnosis of transient ischemic attack by a neurologist. Major bleeding was defined as fatal bleeding, a decrease in the blood hemoglobin level >4 g/dL, the need for transfusion of >2 units of blood, the need for corrective surgery intervention, and intracranial or intraocular bleeding. Outcomes were identified using ICD-9 codes and were verified by chart review. The following ICD-9 codes were used to identify patients and endpoints with verification by chart review: anterior wall MI (410.0-1), ischemic stroke (434), transient ischemic attack (435), blood transfusion (99.0), arterial embolism and thrombosis (444.xx), intracranial hemorrhage (430, 431, 432.x), gastrointestinal bleeding (578), and adverse effect related to therapeutic use of anticoagulants (E934.2). Early discontinuation of warfarin was defined as discontinuation before 90 days of therapy postdischarge. Data were analyzed using SPSS Version 21 (IBM Corporation). Continuous variables are reported as means and standard deviation for normally distributed data and as medians for non–normally distributed data. Dichotomous variables are reported as percentages. Comparisons are considered to be significant if the P value is less than an a priori alpha level of 0.05. Comparisons of continuous variables were made with the use of the Student t test for normally distributed data and the Mann-Whitney U test for non–normally distributed data as appropriate. Dichotomous or categorical data were tested by the use of chi-square or Fisher’s exact tests where appropriate. RESULTS A total of 124 patients met the inclusion criteria, with 80 patients in the DAPT group and 44 patients in the TT group. The median hospital length of stay was 4 days, with a median follow-up of 65 days. The median peak troponin level was 83 ng/mL. Baseline demographics were similar between both groups, except for age. Patients in the DAPT group were 446
Table 1. Baseline demographics Variable Age, median (years)
DAPT (n = 80) TT (n = 44) P value 64
58
0.04
Men
60%
71%
0.25
Hypertension
59%
61%
0.78
Diabetes mellitus
25%
25%
1.00
Dyslipidemia
43%
50%
0.42
Smoking
46%
48%
0.88
Prior myocardial infarction
15%
9%
0.35
Prior percutaneous intervention
15%
11%
0.57
Prior coronary artery bypass graft
5%
0%
0.30
Prior cerebrovascular accident
4%
5%
0.83
Ischemic stroke
3%
0%
0.54
Transient ischemic attack
1%
2%
1.00
Atrial fibrillation
4%
5%
1.00
Heart failure
5%
0%
0.30
Chronic kidney disease
6%
2%
0.42
DAPT indicates dual antiplatelet therapy; TT, triple antithrombotic therapy.
significantly older than patients in the TT group (median age of 64 vs. 58 years, P = 0.04). Most patients were male in both groups (60% in DAPT vs. 70.5% in TT, P = 0.25). Other baseline variables are shown in Table 1. Overall, the insertion of a drug-eluting stent was the most utilized intervention: 71% of patients in the DAPT group received at least one drug-eluting stent, compared with 64% in the TT group (P = 0.38). Clopidogrel was the predominant P2Y12 inhibitor utilized, and patients in the TT group were more likely to be on clopidogrel than patients in the DAPT group (83% vs 96%, P = 0.04). Medications including beta-blockers, statins, and angiotensin-converting enzyme inhibitors were widely used in both groups, as shown in Table 2. The median estimated EF at baseline was 31% in the DAPT group compared with 30% in the TT group (P = 0.36), and anterior akinesis was described in 79% of patients (80% in the DAPT group vs 77% in the TT group, P = 0.72). A follow-up echocardiogram was performed at a median of 49 days in 82% of patients (81.3% of DAPT group vs 97.7% in TT group). The median estimated EF at follow-up was 40% in both groups (P = 0.81). There was a substantial recovery in wall motion abnormality in both groups at follow-up, with 43% described as having apical akinesis compared with 79% at baseline (P < 0.001). Additional information is presented in Table 3. The mean international normalized ratio at discharge was 1.4 (n = 40), with a third of patients (n = 13) receiving anticoagulant bridge therapy with either low-molecular-weight heparin (n = 10) or unfractionated heparin (n = 3). At follow-up, the mean international normalized ratio was 2.4 (n = 34), with an average length of therapy with warfarin in the TT group of 75 days. LVT, stroke, or arterial thrombosis occurred in 4 patients receiving DAPT and in 3 patients receiving TT (5.0% vs 6.8%,
Baylor University Medical Center Proceedings
Volume 28, Number 4
Table 2. Interventions and medications at baseline Intervention/medication Drug-eluting stent
Table 4. Outcomes
DAPT (n = 80)
TT (n = 44)
P value
71%
64%
0.38
Endpoints
DAPT (n = 80)
TT (n = 44)
P value
4 (5.0%)
3 (6.8%)
0.70
Left ventricular thrombus
2 (2.5%)
3 (6.8%)
0.35
Stroke
Primary endpoint
Bare metal stent
21%
23%
0.85
Aspirin
100%
100%
–
2 (2.5%)
0
0.54
300 mg
66%
50%
0.08
Overall reported bleeding
2 (2.5%)
4 (9.1%)
0.18
Major bleeding
1 (1.25%)
0
1.00
Clopidogrel
83%
96%
0.04
Prasugrel
15%
5%
0.14
Ticagrelor
P2Y12 receptor inhibitor
2.5%
0
0.54
Statin
99%
98%
0.38
Beta-blocker
99%
93%
0.13
ACE inhibitor
91%
96%
0.49
Proton pump inhibitor
16%
14%
0.70
H2 receptor antagonist
5%
11%
0.28
ACE indicates angiotensin-converting enzyme; DAPT, dual antiplatelet therapy; TT, triple antithrombotic therapy.
respectively, P = 0.70; Table 4). Patients in the DAPT group had an equal number of incidents of LVT and stroke (2 patients each), whereas there were no reported strokes in patients in the TT group, with LVT being identified in 3 patients. Major bleeding occurred in 1 patient in the DAPT group and none in the TT group, whereas total reported bleeding occurred in 2 patients in the DAPT group and 4 patients in the TT group (2.5% vs 9.1%, respectively, P = 0.18). DISCUSSION When we reviewed the outcomes of patients with anterior STEMI complicated by wall motion abnormalities and depressed EF treated with PCI, we found no significant differ-
Table 3. Echocardiographic findings DAPT Predischarge, n
80
TT
P value
44
Estimated EF (median)
31%
30%
0.36
Apical akinesis
80%
77%
0.72
Apical dyskinesis
3%
11%
0.10
Apical hypokinesis
8%
9%
0.74
65
43
Postdischarge, n Estimated EF (median)
40%
40%
0.81
Apical akinesis
41%
46%
0.65
Apical dyskinesis
4%
2%
1.00
Apical hypokinesis
23%
36%
0.10
DAPT indicates dual antiplatelet therapy; EF, ejection fraction; TT, triple antithrombotic therapy.
October 2015
ence between those who received TT including warfarin and those receiving DAPT alone. There are very few studies that have evaluated the benefits of TT in patients presumed to be at highest risk of developing LVT. In a natural history study of 198 patients admitted for acute MI in the 1980s, LVT developed only in patients with anterior wall MI (1). Stepwise logistic regression analysis identified anterior location of the infarct, decreased left ventricular EF (
Current guidelines recommend triple antithrombotic therapy (TT) consisting of warfarin, aspirin, and a P2Y12 inhibitor following an anterior ST elevation myocardial infarction (STEMI) complicated by extensive wall motion abnormalities. This recommendation, however, is based on data collected before percutaneous coronary intervention (PCI) became the standard of care for the treatment of STEMI. We designed a retrospective study of patients who received PCI for anterior STEMI over an 8-year period to compare rates of thromboembolic and bleeding events between patients receiving dual antiplatelet therapy (DAPT) and those receiving TT, including warfarin. Patients were included if the predischarge echocardiogram showed extensive wall motion abnormality and an ejection fraction ≤35%. Patients with known left ventricular thrombus were excluded. A total of 124 patients met the criteria, with 80 patients in the DAPT group and 44 in the TT group. The median age was 58 years in the TT group and 64 years in the DAPT group (P < 0.04), with an average ejection fraction of 31%. Thromboembolic events occurred in 4 patients (5%) in the DAPT group compared with 3 patients (6.8%) in the TT group (P = 0.70). Bleeding occurred in 2 patients in the DAPT group and 4 patients in the TT group (2.5% in DAPT vs. 9.1% in TT group, P = 0.18). No differences in rates of clinical embolism or left ventricular thrombus were found. Our data support recent findings that warfarin may not be indicated for patients following PCI for anterior STEMI, even when significant wall motion abnormalities and reduced ejection fraction ≤35% are present.
A
cute thromboembolic events due to left ventricular thrombus (LVT) formation, particularly in patients with reduced ejection fraction (EF), remain a risk for patients surviving an anterior ST elevation myocardial infarction (STEMI) (1). The reported incidence of LVT formation and subsequent embolization varies based on the timing of the echocardiographic examination and the diagnostic, anticoagulation, and reperfusion strategies utilized in managing the initial presentation but is noted to range from 0 to as high as 86% (1–9). Warfarin as a prophylactic strategy is therefore utilized and suggested in guidelines based on data derived from pooled results of studies done before catheter-based treatment of STEMI was prominent (10, 11). A recent report by Le May et al has suggested that warfarin treatment might be unnecessary in patients managed by primary PCI and dual antiplatelet therapy (DAPT) (12). The potential adequacy of DAPT alone Proc (Bayl Univ Med Cent) 2015;28(4):445–449
was also shown in a small study that showed no advantage to a triple therapy (TT) regimen involving aspirin, a P2Y12 inhibitor, and warfarin when compared with DAPT with aspirin and a P2Y12 inhibitor in preventing LVT and systemic embolism (13). Given the uncertain benefit and known bleeding risk associated with TT (14), we conducted a retrospective analysis spanning 8 years to compare the rates of LVT formation and thromboembolic events in patients with STEMI with EF ≤35% managed with DAPT alone versus TT. METHODS This was a retrospective, single-center study of patients presenting with anterior wall myocardial infarction (MI) between January 2003 and November 2012 with additional follow-up within 16 weeks of initial discharge at a large academic medical system which serves as the primary STEMI PCI center in the Central Texas region. The study timeline was selected based on availability of electronic medical records for review. Study data were abstracted from the electronic medical record system, which contained both inpatient and outpatient visits. The study received approval from the institutional review board. Patients were identified as having anterior wall MI based on documentation obtained using the ICD-9 codes for initial episode of care for acute anterior MI (410.0, 410.1). These codes were verified on the hospital discharge summary during manual electronic chart review. Subjects had to meet the following inclusion criteria: received primary PCI (including rescue PCI for failed lytic therapy); received aspirin and an additional P2Y12 inhibitor (clopidogrel, prasugrel, or ticagrelor); had a predischarge echocardiogram showing extensive wall motion abnormalities (akinetic or hypokinetic segments); and had an EF ≤35%. Patients were excluded if they did not survive to hospital discharge, required anticoagulation for other indications (atrial fibrillation or valvular disease), had no additional From the Department of Pharmacy Practice, College of Pharmacy, Texas A&M Health Science Center and Baylor Scott & White Health, Temple, Texas (Oyetayo); the Division of Cardiology (Slicker, De La Rosa, Michel, Chiles) and Department of Internal Medicine (Lane, Langsjoen, Patel, Brough), College of Medicine, Texas A&M Health Science Center, and Baylor Scott & White Health, Temple, Texas. Corresponding author: Jeffrey Michel, MD, Baylor Scott & White Health, 2401 South 31st Street, MS-33-ST156, Temple, TX 76508 (e-mail: [email protected]). 445
follow-up within 16 weeks of initial discharge in the system, or had identified thrombus on predischarge echocardiogram. A 16-week follow-up was utilized since current guidelines recommend 3 months of therapy if actively prophylaxing against LVT formation. Patients were treated according to the discretion of the admitting cardiologists at the time of admission. Patients were classified into two groups based on the receipt of oral anticoagulation with warfarin. Patients receiving warfarin therapy in addition to aspirin and an additional P2Y12 agent (clopidogrel, prasugrel, or ticagrelor) at discharge were classified as the TT cohort, whereas patients receiving dual therapy with aspirin and an additional P2Y12 agent (clopidogrel, prasugrel, or ticagrelor) were identified as the DAPT cohort. The primary study outcome was the first occurrence of the composite of LVT, cerebrovascular accident, or systemic embolism. The primary safety endpoint was major bleeding. Other outcomes included the rate of occurrence of the individual components of the primary outcome and total reported bleeding. LVT was defined as a report of possible, probable, or definite thrombus on an echocardiogram. Thromboembolic complications were identified as clinical manifestation of acute cerebral or peripheral ischemia diagnosed with objective testing or the clinical diagnosis of transient ischemic attack by a neurologist. Major bleeding was defined as fatal bleeding, a decrease in the blood hemoglobin level >4 g/dL, the need for transfusion of >2 units of blood, the need for corrective surgery intervention, and intracranial or intraocular bleeding. Outcomes were identified using ICD-9 codes and were verified by chart review. The following ICD-9 codes were used to identify patients and endpoints with verification by chart review: anterior wall MI (410.0-1), ischemic stroke (434), transient ischemic attack (435), blood transfusion (99.0), arterial embolism and thrombosis (444.xx), intracranial hemorrhage (430, 431, 432.x), gastrointestinal bleeding (578), and adverse effect related to therapeutic use of anticoagulants (E934.2). Early discontinuation of warfarin was defined as discontinuation before 90 days of therapy postdischarge. Data were analyzed using SPSS Version 21 (IBM Corporation). Continuous variables are reported as means and standard deviation for normally distributed data and as medians for non–normally distributed data. Dichotomous variables are reported as percentages. Comparisons are considered to be significant if the P value is less than an a priori alpha level of 0.05. Comparisons of continuous variables were made with the use of the Student t test for normally distributed data and the Mann-Whitney U test for non–normally distributed data as appropriate. Dichotomous or categorical data were tested by the use of chi-square or Fisher’s exact tests where appropriate. RESULTS A total of 124 patients met the inclusion criteria, with 80 patients in the DAPT group and 44 patients in the TT group. The median hospital length of stay was 4 days, with a median follow-up of 65 days. The median peak troponin level was 83 ng/mL. Baseline demographics were similar between both groups, except for age. Patients in the DAPT group were 446
Table 1. Baseline demographics Variable Age, median (years)
DAPT (n = 80) TT (n = 44) P value 64
58
0.04
Men
60%
71%
0.25
Hypertension
59%
61%
0.78
Diabetes mellitus
25%
25%
1.00
Dyslipidemia
43%
50%
0.42
Smoking
46%
48%
0.88
Prior myocardial infarction
15%
9%
0.35
Prior percutaneous intervention
15%
11%
0.57
Prior coronary artery bypass graft
5%
0%
0.30
Prior cerebrovascular accident
4%
5%
0.83
Ischemic stroke
3%
0%
0.54
Transient ischemic attack
1%
2%
1.00
Atrial fibrillation
4%
5%
1.00
Heart failure
5%
0%
0.30
Chronic kidney disease
6%
2%
0.42
DAPT indicates dual antiplatelet therapy; TT, triple antithrombotic therapy.
significantly older than patients in the TT group (median age of 64 vs. 58 years, P = 0.04). Most patients were male in both groups (60% in DAPT vs. 70.5% in TT, P = 0.25). Other baseline variables are shown in Table 1. Overall, the insertion of a drug-eluting stent was the most utilized intervention: 71% of patients in the DAPT group received at least one drug-eluting stent, compared with 64% in the TT group (P = 0.38). Clopidogrel was the predominant P2Y12 inhibitor utilized, and patients in the TT group were more likely to be on clopidogrel than patients in the DAPT group (83% vs 96%, P = 0.04). Medications including beta-blockers, statins, and angiotensin-converting enzyme inhibitors were widely used in both groups, as shown in Table 2. The median estimated EF at baseline was 31% in the DAPT group compared with 30% in the TT group (P = 0.36), and anterior akinesis was described in 79% of patients (80% in the DAPT group vs 77% in the TT group, P = 0.72). A follow-up echocardiogram was performed at a median of 49 days in 82% of patients (81.3% of DAPT group vs 97.7% in TT group). The median estimated EF at follow-up was 40% in both groups (P = 0.81). There was a substantial recovery in wall motion abnormality in both groups at follow-up, with 43% described as having apical akinesis compared with 79% at baseline (P < 0.001). Additional information is presented in Table 3. The mean international normalized ratio at discharge was 1.4 (n = 40), with a third of patients (n = 13) receiving anticoagulant bridge therapy with either low-molecular-weight heparin (n = 10) or unfractionated heparin (n = 3). At follow-up, the mean international normalized ratio was 2.4 (n = 34), with an average length of therapy with warfarin in the TT group of 75 days. LVT, stroke, or arterial thrombosis occurred in 4 patients receiving DAPT and in 3 patients receiving TT (5.0% vs 6.8%,
Baylor University Medical Center Proceedings
Volume 28, Number 4
Table 2. Interventions and medications at baseline Intervention/medication Drug-eluting stent
Table 4. Outcomes
DAPT (n = 80)
TT (n = 44)
P value
71%
64%
0.38
Endpoints
DAPT (n = 80)
TT (n = 44)
P value
4 (5.0%)
3 (6.8%)
0.70
Left ventricular thrombus
2 (2.5%)
3 (6.8%)
0.35
Stroke
Primary endpoint
Bare metal stent
21%
23%
0.85
Aspirin
100%
100%
–
2 (2.5%)
0
0.54
300 mg
66%
50%
0.08
Overall reported bleeding
2 (2.5%)
4 (9.1%)
0.18
Major bleeding
1 (1.25%)
0
1.00
Clopidogrel
83%
96%
0.04
Prasugrel
15%
5%
0.14
Ticagrelor
P2Y12 receptor inhibitor
2.5%
0
0.54
Statin
99%
98%
0.38
Beta-blocker
99%
93%
0.13
ACE inhibitor
91%
96%
0.49
Proton pump inhibitor
16%
14%
0.70
H2 receptor antagonist
5%
11%
0.28
ACE indicates angiotensin-converting enzyme; DAPT, dual antiplatelet therapy; TT, triple antithrombotic therapy.
respectively, P = 0.70; Table 4). Patients in the DAPT group had an equal number of incidents of LVT and stroke (2 patients each), whereas there were no reported strokes in patients in the TT group, with LVT being identified in 3 patients. Major bleeding occurred in 1 patient in the DAPT group and none in the TT group, whereas total reported bleeding occurred in 2 patients in the DAPT group and 4 patients in the TT group (2.5% vs 9.1%, respectively, P = 0.18). DISCUSSION When we reviewed the outcomes of patients with anterior STEMI complicated by wall motion abnormalities and depressed EF treated with PCI, we found no significant differ-
Table 3. Echocardiographic findings DAPT Predischarge, n
80
TT
P value
44
Estimated EF (median)
31%
30%
0.36
Apical akinesis
80%
77%
0.72
Apical dyskinesis
3%
11%
0.10
Apical hypokinesis
8%
9%
0.74
65
43
Postdischarge, n Estimated EF (median)
40%
40%
0.81
Apical akinesis
41%
46%
0.65
Apical dyskinesis
4%
2%
1.00
Apical hypokinesis
23%
36%
0.10
DAPT indicates dual antiplatelet therapy; EF, ejection fraction; TT, triple antithrombotic therapy.
October 2015
ence between those who received TT including warfarin and those receiving DAPT alone. There are very few studies that have evaluated the benefits of TT in patients presumed to be at highest risk of developing LVT. In a natural history study of 198 patients admitted for acute MI in the 1980s, LVT developed only in patients with anterior wall MI (1). Stepwise logistic regression analysis identified anterior location of the infarct, decreased left ventricular EF (
